Slide type mechanical pencil

ABSTRACT

A slide type mechanical pencil, comprising a body having the desired length and diameter, a tubular push-rod slidably accommodated in said body and continuously urged towards the rear thereof. A chuck is supported by said push-rod, a gripping member is fixedly provided in the body opposite the tapered part of the chuck, and a slider is accommodated in the front part of the body in such a manner that it can slide a fixed length. By cooperative working of said chuck, said gripping member and said slider, automatic exposure of the lead for continuous writing is made possible.

United States Patent [191 Torii et al.

1451 Apr. 16, 1974 SLIDE TYPE MECHANICAL PENCIL [75] Inventors: OsamuTorii; Sugako Torii, both of Kyoto; Yasuyuki Hashimoto, I-lyogo, all ofJapan [73] Assignees: Ancos Co., Ltd.; The Skater Fountain Pen Co.,Ltd., both of Osaka, Japan [22] Filed: Mar. 24, 1971 21 Appl. No.:121,492

[52] [1.8. CI. 401/58, 401/65, 401/93 [51] Int. Cl. 543k 21/16 [58]Field of Search 401/65, 67, 58, 92-94 [56] References Cited UNITEDSTATES PATENTS 11/1970 Sakamotomm .;-.....-40l/67 10/1949 1 Mustard401/67 3,205,862 9/l965 Brewer 401/58 Primary Examiner-Lawrence CharlesAttorney, Agent, orFirm-Wende:roth, Lind & Ponack [5 7] ABSTRACT 5Claims, 3 Drawing Figures PQATENTEDAPR :6 e914 SHEET 1 BF 2 INVENTORSOSAMU TORII SUGAKO TORII and YASUYUKI HASHIMO'IO ATTORNEY 5 PATENTEDAPR16 I974 sum 2 or z OSAMU TORII, SUGAKO TORII and YASUYUKI HASHIMOTO,

INVENTOR s BY a mludi,

ATTORNEYS SLIDE TYPE MECHANICAL PENCIL This invention relates to a slidetype mechanical pen cil, wherein a slider recedes automatically at thesame that rate the lead wears away, due to writing pressure, and thuscontinuous writing is possible without the necessity of frequentlypushing out a lead by pressing the rear end of the pencil with a thumb.When a lead of a fixed length or the length corresponding to theslidable length of the slider has worn away, a further length of thelead corresponding to the slidable length of the slider can be pushedout at once, together with the slider, by pressing the rear end of thepencil. More particularly, this invention relates to a pencil of slidetype comprising a tubular body having a desired length and desiredinternal and external diameters, a tubular pushrod which is slidablymounted in said tubular body and which carries at its front end a chuckto hold the lead, a coiled spring which continuously urges said push-rodto rearward, a gripping member provided in said tubu- 5 to be describedhereinafter, so as to continuously lar body which, when the push-rodrecedes, hits on the tapered part of the chuck and throttles the chuck,and a slider which is slidably accommodated in the front end of thetubular body and carries a lead gripping means to hold the lead.According to this arrangement, in proportion to the consumption of thelead during writing, the slider recedes automatically due to the writingpressure, making it possible to continue writing without the need offrequently pushing out a lead during writing. Furthermore, when a fixedlength of a lead or the length corresponding to the slidable length ofthe slider has been consumed, another fixedlength of the lead can bepushed out, together withthe slider. The pencil according to the presentinvention is so designed that the slider slides smoothly without play asdescribed hereinafter, with the resultthat a lead is entirely free frombreaking off. Furtheremore, it has the advantages that a lead'can beuseduntil it becomes the accompanying drawings showing an embodiment ofthe present invention, in which:

FIG. 1 is a longitudinal sectional view of the pencil, according to thepresent invention, which is ready for writing with its slider forward. i

FIG. 2 is a longitudinal sectional view of the same pencil with itsslider receded entirely due to writing pressure, in proportion to thewearing of a lead, and

FIG. 3 is a longitudinal sectional view of the same pencil with itsslider and lead pushed out. In the drawings, numeral 1 denotes apipe-shaped body made of metal, synthetic resin or other material andhaving a desired length and a desired diameter. This body comprises ametallic cap 1a, a front axis 1b and a rear axis- 1c, all connectedtogether by screwthreading. Provided through this body is a tubularpush-rod 2 (alsoserving as a lead-case), at the tip of which is provideda lead-guide 3 whereby leads 1.. in the lead case 2 are fed outone byone. Connected to the tip of this lead-guide 3 is a chuck 4 split inthree parts to grip a lead at its top portion. This chuck 4 is notlimited to a three-split type but can be split into any desired pluralparts. At the rear part of the lead-case or the tubular push-rod 2 is anannular bulge 2a. A cap C is put on the push-rod 2 until it hits thebulge 2a so as to act as a pushing member. Detachably mounted in theextreme rear end of the push-rod 2 is an eraser R held by a metallicpiece M. Stuck in this eraser R is a cleaner-pin P which can be used toclean the top part of the slider or the chuck as described hereinafter.A coiled spring S is provided around the periphery of the leadguide 3,between a projection 3a of the lead-guide. 3.

and a stepped portion 5b of a gripping member receiver urge the push-rod2 (and the chuck) to recede. Other arrangements could be adopted for thesame purpose. For example, a coiled spring S could be sandwiched betweena stepped portion l d provided in the body and the bulge 2a mentionedabove. A gripping member 6 is provided at the position corresponding tothe threesplit chuck 4 within the body 1. This gripping member 6 is sodesigned that it is held within the body by a gripping member receiver 5having a fixing member 5a by which it is fixed to the body. Formedinside the abovementioned gripping member receiver 5 is a steppedportion 5b to receive the coiled spring S. The gripping member 6 isconnected to the from inner surface of the gripping member receiver 5.This gripping member 6 should be made of such material and in such shape(as with'the gripping member receiver 5, which is made integral with thefixing partSa. The fixing member Sais appropriately fixed in the body.

A slider 7 is slidably provided at the front portion of the body 1,between the body 1 and the gripping member receiver 5. The top portionofthe slideris made smaller to correspond to the inner surface of thetapered metallic cap. At the tip of the slider is provided a thin pipe7a with its tip rounded, through which a lead can be passed without anytrouble. The diameter of the pipe 7a is such that it can be slid in andout of the metallic cap while it is in sliding contact with the innersurface of the bore at the tip of the metallic cap 1a. Alternatively thetip portion of the slider 7 can be made with a smaller diameter so thatit can be slid in and out of the metallic cap (in this case, therefore,a larger portion of the slider is always kept within the metallic cap).A lead-holding member 7b which is made of rubber, synthetic resin orother elastic material and which lightly holds a lead ispressed into theinner surface at i the tip of the. slider.

In the pencil of the above-mentioned construction, if writing iscontinued in such a condition that the slider,

together with a lead, is in the forward state as shown in FIG. 1, thethin pipeat the tip of the slider runs on the surface of the writingpaper, together with a lead which is gripped by the three-split chuck.Accordingly, in proportion to the amount of wearing of the lead,theslider recedes automatically against the gripping force of the leadholding member 7b, whereby continuous writing is made possible untilthelead of a fixed length in the slider is used up, without thenecessity of pushing out additional lead. When the lead within theslider has worn away an amount equal to the slidable length of theslider. and the pencil is in the state as shown by FIG. 2, the pushgiven to the pencil or pressing of the cap C of the push-rod in thedirection of the arrow Y, causes the push-rod 2 to shift by one stroketoward the direction of the tip of the body. At this time, the chuck 4is released from engagement with the gripping member 6 and accordinglyreleases the lead from being gripped, whereupon the slider advances byits own weight or due to the force in the direction Y appliedcontinuously to .the push-rod 2, the tip of the chuck hits upon andpushes the inner surface of the slider 7, which causes the slider 7 tomove forward by one stroke, together with the lead L which is heldlightly by the lead-holding member.

In the embodiment shown, the slider7 is slidably provided within themetallic cap la which is screwthreaded into the tip of the body 1 andits smaller part at the top end hits the inner surface of the metalliccap, causing the thin pipe 7a to project from the metallic cap. However,it is possible to make the rear end of the slider larger so that thethin pipe and the tip of the slider may project from a metallic caphaving a larger bore.

The lead-holding member 7b may be made of most any material having ahigh coefficient offriction, for example, soft rubber, and can adoptvarious holding structures. 7

According to the present invention, by pressing the push-rod 2 a lead ispushed out by a .fixed length, together with the slider, and theconsumption of a lead during writing is covered by correspondingautomatic recession of the slider and resultant automatic exposure ofthe lead. Thus, automatic exposure of a lead during writing can beexecuted by the combination. of the slider and the push-rod. In moredetail, by the sliding of the push-rod, a fixed length of a lead can bepushed forward, together with the slider. The slider then recedesautomatically little by the little by writing pressure at the same rateas the lead wears away. Furthermore, since the slider protects the leadup to the lead-point, the lead is prevented from breaking off duringwriting.

What is claimed is: l

1. A slide type mechanical pencil comprising a tubular body memberhaving predetermined interior and chuck and said gripping member.

l l l l exterior diameters and a tapered metallic cap positioned at itsforward end, a tubular push rod slidably accommodated in said body andbeing continuously urged towards the rear end thereof, a chuckmembersupported by said push rod and having a tapered section facingrearwardly, a gripping member fixedly secured to said body memberopposite said chuck member, said gripping member having a tapered innersection for receiving the tapered section of said chuck member, and aslider member carrying a lead holding member positioned at the forwardend of said body member, said slider member being capable of slidingforwardly and rearwardly for a fixed length, whereby by cooperativeworking of said chuck member, said gripping member and said slidermember, automatic feeding of lead to the pencil point for continuouswriting is made possible.

2. A slide type mechanical pencil as claimed in claim 1 wherein saidslider member has a bore at the forward end thereof through which a leadcan be passed and a thin pipe to protect the lead positioned within saidbore, said pipe being automatically retractable, together with saidslider, in proportion to the wearing of the lead during writing so astoeffect an automatic supply of said lead.

' 3. A slide type mechanical pencil as claimed in claim 2 wherein saidslider member is tapered at its forward end to correspond to the taperedinner part of said metallic cap, and the forward movement of said thinpipe protecting said lead is limited by the tip of said slider hittingthe inner surface of said metallic cap.

4. A slide type mechanical pencil as claimed in claim 1 wherein a coiledspring is positioned between said push rod and said body member tocontinuously urge said push rod rearwardly.

5. A slide type mechanical pencil as claimed in claim 1 wherein saidslider member has a tapered forward section and a hollow cylindricalrearward section, said cylindrical rearward section normally surroundingsaid

1. A slide type mechanical pencil comprising a tubular body memberhaving predetermined interior and exterior diameters and a taperedmetallic cap positioned at its forward end, a tubular push rod slidablyaccommodated in said body and being continuously urged towards the rearend thereof, a chuck member supported by said push rod and having atapered section facing rearwardly, a gripping member fixedly secured tosaid body member opposite said chuck member, said gripping member havinga tapered inner section for receiving the tapered section of said chuckmember, and a slider member carrying a lead holding member positioned atthe forward end of said body member, said slider member being capable ofsliding forwardly and rearwardly for a fixed length, whereby bycooperative working of said chuck member, said gripping member and saidslider member, automatic feeding of lead to the pencil point forcontinuous writing is made possible.
 2. A slide type mechanical pencilas claimed in claim 1 wherein said slider member has a bore at theforward end thereof through which a lead can be passed and a thin pipeto protect the lead positioned within said bore, said pipe beingautomatically retractable, together with said slider, in proportion tothe wearing of the lead during writing so as to effect an automaticsupply of said lead.
 3. A slide type mechanical pencil as claimed inclaim 2 wherein said slider member is tapered at its forward end tocorrespond to the tapered inner part of said metallic cap, and theforward movement of said thin pipe protecting said lead is limited bythe tip of said slider hitting the inneR surface of said metallic cap.4. A slide type mechanical pencil as claimed in claim 1 wherein a coiledspring is positioned between said push rod and said body member tocontinuously urge said push rod rearwardly.
 5. A slide type mechanicalpencil as claimed in claim 1 wherein said slider member has a taperedforward section and a hollow cylindrical rearward section, saidcylindrical rearward section normally surrounding said chuck and saidgripping member.